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/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1998-2016. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* %CopyrightEnd%
*/
#ifndef _EICODE_H
#define _EICODE_H
/*
* The following functions are used to encode from c native types directly into
* Erlang external format. To use them, you need
*
* - a destination buffer
* - an index counter
* - some data
* - an idea of how you want to represent the data as an Erlang term.
*
* You can encode exactly one (1) term into the buffer if you are
* going to transmit it to Erlang. Do the following:
*
* 1. Set your index to 0
* 2. Encode the version into the buffer: ei_encode_version(buf,&index);
* The function has now advanced index so the next item can be encoded.
* 3. Encode your term:
*
* Encoding non-compound types (i.e. not lists or tuples) is
* straightforward. Just do it!
*
* Encoding tuples is done by first encoding the tuple header (it
* contains the arity) and then encoding the tuple elements in
* sequence.
*
* Encoding lists is done by first encoding the list header (it
* contains the arity) and then encoding the list elements in
* sequence, and finally encoding an empty list.
*
* After all this, the index counter will tell you how much buffer you
* used. If you really need to know in advance how big the buffer
* should be, go through the same steps but with a NULL buffer. No
* attempt will be made to modify the buffer, but index will be
* updated as though you really did encode something.
*/
/* encode the given object into buf[index] as 'type'. 0 is
* returned and index is updated to the position for the next item. if
* buf == NULL, no data is actually copied, but index is updated to
* indicate the number of bytes that would have been necessary.
*/
/* FIXME where do we put these..... */
erlang_big *ei_alloc_big(int arity);
void ei_free_big(erlang_big *b);
#endif /* _EICODE_H */
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